Printing or otherwise labeling stuff helps tremendously to organize life in general, and it is even an obsession for some folks. However, as much as it may be fun to think of new names and decide what font or colors to use – certain technical aspects are not so easy to overcome and require a more serious approach.
Printing on clean, white paper is rather straightforward, the adhesive surface soaks up ink and it permanently changes color, leaving a clear mark on the surface. You can place it in a printing press, apply some pressure with appropriate metal or wooden letters, and there you go. But what happens if the surface isn’t flat, but curved? What happens if the material is sleek and doesn’t absorb ink? Or if it is very hard, such as metal?
Many modern materials and appliances have different characteristics than paper but still require some printing. And to do this, certain preparations need to be made.
Printing Technology
Even before Guthemberg’s great invention people have been marking things and writing symbols down. But this process was usually slow and tedious if one wanted to secure consistency. But the printing press, in the way we understand it today, revolutionized the way we “write down” things, and introduced a new technology – printing. Previously made letter stamps could be arranged in whatever way to form an entire page and then stamped over paper or a similar material. The ink used played and still plays, a significant role.
Etching is another form of printing, but one where lines or whole areas are incised into metal, using acid. This is then used as a plate for further printing, though the original can also be a stand-alone piece, especially if it is highly polished later on. The latest in terms of technological advancement is using lasers to apply an image on paper or other surfaces.
Why Surface Treatment Matters
Probably the main factor that determines how hard it is to print is the surface itself. Proper preparation makes all the difference between a proper finish and a lousy one. Applying plasma 3D solutions on non-flat surfaces, especially on materials that cannot go into a press, is one good option. Another, if that is not possible, is to bring the material as close as possible to a classical printing condition first.
Curved surfaces, for example, are best printed on while flat first (as is the case for labels on bottles, for example), though that sometimes needs to take into account the amount of curvature it will have, so the text doesn’t get too deformed afterward. Another example is printing, or embossing, on glass. Glass is very fragile so any applied pressure must be very light – meaning either the chemistry of the ink must be very adhesive, or the glass must be modeled while hot and in a softer state.
Surface Treatment on Various Materials
Depending on what you plan on printing, and on what material, you will encounter several issues, most of which are solved with a proper approach to surface preparation and treatment of the material itself.
Rubber is a natural material made from a sort of resin, mostly known as latex, that is harvested in a process called “tapping”. It has both great stretch and is water-proof, making it a versatile material in any industrial process. Because it has a relatively low tolerance for temperature it cannot be pressed with great force during printing but must be lightly stamped or laser printed.
Metal can come in many shapes and sizes, from steel to copper, and so forth, but what characterizes it is that it is a shiny and strong material. Ideal for making durable objects that should be labeled appropriately. Every metal surface, before printing, must be degreased and brought to the desired polish. This can be done with a simple degreaser (such as soap) and a tablecloth, but if there is rust present you must use some sort of abrasive.
Plastics are too versatile to be placed into one category but are non the less used frequently in our everyday lives. Their surfaces usually need better adhesion properties to be easily printed on, something that can be done using coatings, or by applying stickers on top of it.
It is rather easy to print on any surface once you know the basics of how printing works. Sure, some will be more difficult and will require more preparation, but an assembly and packaging line should be designed with this in mind and made do with anything that comes their way.
